Dispensing cap with improved tightness

ABSTRACT

A dispensing cap which fits on a container containing a fluid product. The cap includes a body provided with a dispensing orifice and a hinged lid which is hinged to the body about an axis. The body and lid are made of a rigid or semi-rigid material. The lid includes a plugging pip for plugging the dispensing orifice when the lid is closed. A coating of elastomeric material is arranged on the outer wall of the pip to produce a seal between the pip and the orifice when the lid is closed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dispensing cap intended to be fittedto a container containing a fluid product to be dispensed, and to adispensing assembly equipped with this cap. It is equipped with astoppering system which can be opened for dispensing the product, andclosed for keeping it.

2. Discussion of the Background

Containers fitted with caps of this kind are customarily used in variousfields, for storing and dispensing liquid products, for example in thefields of cosmetics, foodstuffs, household, pharmacy or personalhygiene. These products are, in particular, shampoos, antiseptics,household cleaners, or washing-up products. Thanks to the use of a capof this kind, on the one hand, it is possible, to prevent the productfrom spilling out during transport and storage and, on the other hand,the product is protected from dirt from the outside. Furthermore, byusing such a cap the user can easily and in a controlled way dispensethe product contained in the container.

More particularly, the present invention relates to a cap comprising aproduct-dispensing orifice and a hinged lid, the system for stopperingthe orifice consisting of a pip borne by the lid and designed to closethis orifice.

The pip introduced into the dispensing orifice needs to fulfil severalfunctions; it must guarantee a good seal; the force required to open itmust be reasonable; and, upon opening, an explosive noise must not beproduced. These qualities need to be provided throughout the use of theproduct. Now, with the materials such as polyethylene or polypropylene,commonly used for injection-moulding such caps, dimensional adjustmentis very tricky because the tolerances need to remain tighter than 0.05mm, especially as there is a risk of additional deformation occurringduring removal from the mould. Furthermore, under intense use, andthrough wear of the pip and/or of the orifice, this pip no longer entersthe orifice with friction, and leaks of product can therefore occur.

A dispensing cap of the kind mentioned hereinabove is described, forexample, in FR-A-2,662,144. This document describes a dispensing capcomprising a dispensing orifice and a hinged lid equipped with a hollowpip, intended to stopper the dispensing orifice when in the storageposition, this pip being in the form of a cylindrical skirt. Accordingto this document, the dispensing orifice is made in a flat portion, atright angles to the longitudinal axis of the cap, this portion beingmade of thermoelastic rubber.

This cap of the prior art has the drawback that when the lid is closed,a relatively high amount of force is needed to engage the pip in thedispensing orifice. This is because during the closure operation, thepip is in contact with the edge of the orifice, and before it engages inthe orifice, it pushes the said rubber portion back.

There is also known, from U.S. Pat No. 5,169,035, a cap similar to theaforementioned cap, the dispensing orifice being made by an annularcomponent made of elastomer, which is clipped into an opening in theupper face of the cap and is able to be plugged by a pip carried by thelid articulated to the cap.

Although the cap according to U.S. Pat. No. 5,169,035 makes it possibleto obtain leaktight stoppering of the dispensing orifice by the pip, itdoes have the following drawbacks: on the one hand, the annularelastomer component has to be quite thick to allow it to be held in theopening of the cap; and on the other hand, the choice of elastomers thatcan be used for producing the annular piece is limited. This is becausewith a view to both flexible and leaktight engagement of the pip in thedispensing orifice it would be desirable to use so-called “soft”elastomers (that is to say elastomers with a hardness of less than about60 Shore A). Now, to ensure that the annular elastomer component is heldcorrectly in place in the opening of the cap, this material has to havea hardness in excess of 60 Shore A, which is prejudicial to the desiredflexible operation and desired sealing of the cap. Furthermore, usingsuch a material, the dimensional tolerances on the pip and thetolerances on positioning it with respect to the dispensing orifice maynot be very well met. Finally, to mount the annular elastomer componentin the orifice from inside the cap is a relatively complicated operationrequiring special appropriate tooling.

SUMMARY OF THE INVENTION

It is a first object of the present invention to provide a dispensingcap which operates flexibly when being opened or closed, under goodconditions of sealing and the cost of which is competitive.

A second object of the invention is to provide a dispensing cap forwhich it is easy to adjust the tolerances on the dimensions of the pipand/or of the dispensing orifice and any moulding/demoulding defects ofwhich can be compensated for. It is a further object of the invention tocreate a particularly well sealed stoppering system, which resists wearthroughout the life of the product and operates flexibly, and is easy toopen and close. Furthermore, the invention also targets the use oforifices of non-circular cross-section, hitherto unknown in theaforementioned fields of use.

The objects mentioned hereinabove are achieved by depositing a coatingof elastomeric material on the outer wall of the pip. Depositing thiscoating, assuming it is achieved by duplex-injection or by overmouldingonto the pip, is easier to achieve than producing, as in the prior art,a dispensing orifice made in a region made of elastomer. Furthermore,producing a coating on the outer wall of the pip makes it possible, onthe one hand, to produce this coating as a thin layer, and thereforemake a saving on material, and, on the other hand, to use particularlyflexible elastomers (with a hardness of less than 60 Shore A), whichmakes the cap flexible to use and provides a perfect seal.

Thus, a first aspect of the invention relates to a dispensing capintended to be fitted to a bottle containing a fluid product, comprisinga body provided with a dispensing orifice and with a hinged lidarticulated to the body about an axis, the body and the lid being madeof a rigid or semi-rigid material, this lid being provided with aplugging pip intended to plug the dispensing orifice, in the storageposition. According to the invention, a coating of elastomeric materialis arranged on the outer wall of the pip, to produce a perfect sealbetween the pip and the orifice when the lid is closed in the saidstorage position.

Another aspect of the invention consists of a dispensing assemblycomprising a container of a product, equipped with a cap in accordancewith the first aspect.

In general, the container equipped with such a cap consists of a fairlyflexible bottle, or alternatively a compressible tube. As a preference,the container has a neck onto which the dispensing cap is fixed byscrewing, snap-fastening, overmoulding, welding or any other knownmeans.

The product to be dispensed can flow out under its own weight and is,for example, shampoo or a body milk with a viscosity generally within arange from 50 mPa.s to 5 Pa.s or alternatively a powdered product.

The dispensing orifice may have a circular, oval, polygonal or elongatecross-section, the cross-section section of the pip complementing thatof the orifice. Thanks to the invention, it is conceivable for orifices,especially those with a non-circular cross-section to be produced,without this resulting in sealing problems.

Thanks to the flexibility of the coating, minor defects in thepositioning of the pip with respect to the orifice can be compensatedfor. The same is true, for differences in respective diameters of theorifice and of the pip. In particular, when there is the desire to makeorifices of non-circular shape, for example in the shape of a star orflat strip, a good seal can be obtained by arranging a coating ofelastomeric material on the external wall of the pip, while at the sametime ensuring that the opening and closing of the dispensing orificewill be flexible.

Advantageously, the outer coating on the pip has a thickness of fromabout 0.1 mm to about 3 mm.

According to another advantageous feature of the invention, it ispossible to produce a hollow pip, formed of a cylindrical skirt. In thiscase, the internal volume of the pip may be filled with flexiblematerial. This is advantageous, because it avoids temporarily trappingresidual product inside the pip, which product could run outunintentionally as the lid is opened and dirty the work surface.

Advantageously, the lid is articulated to the cap body using a hingepivoting about an axis. This hinge is preferably a film hinge mouldedintegrally with the cap body and lid.

As a preference, the cap and its lid are made of a rigid or semi-rigidthermoplastic, for example polypropylene or either high or low densitypolyethylene.

According to a first embodiment, the flexible material may be athermoplastic elastomer physico-chemically compatible with the rigid orsemi-rigid material and capable of forming, when the cap is produced,for example by duplex injection or overmoulding, a link by fusion withthe rigid or semi-rigid material.

According to this embodiment, this thermoplastic elastomer isadvantageously chosen from the group of polyether block amideelastomers, polyvinyls; terpolymers of ethylene, propylene and a diene(EPDM); styrene-ethylene-butadiene block copolymers (SEBS-SIS).

According to another embodiment, the flexible material is chosen fromnatural or synthetic rubbers, or alternatively from silicone rubbers.

According to yet another embodiment, the said coating consists of anattached part made of elastomer, deposited on the outer wall of the pipby assembly.

Advantageously, this assembly may be achieved, for example, bysnap-fastening, bonding, welding, drawing, upset heading or any otherappropriate means. Mounting it by drawing is particularly advantageousin that it allows thinner thicknesses.

Advantageously, the flexible material is chosen such that the coatinghas a hardness of from 20 Shore A to 90 Shore A, and preferably of from30 Shore A to 60 Shore A.

The cap of the invention may be equipped with a certain number ofadditional features, described below.

Thus, part of the body and/or of the lid may be provided with a grippingregion comprising a region made of flexible material, produced at thesame time as the coating on the pip, by overmoulding or duplex injectionof the cap body. This gripping region makes the lid easier to open andclose on account of the non-slip effect displayed by certain elastomers.This is advantageous, especially when the user has wet hands, forexample when in the shower.

Furthermore, the body of the cap may have an annular gasket made offlexible material, in sealed contact with a peripheral edge of the lid,when the lid is flipped down.

It is also conceivable to provide a spring “toggle effect” hinge byusing at least one connecting element made of flexible material, whichis elastically deformable in extension, forming a spring. In this case,one of the ends of the connecting element is secured to the body, andthe other is secured to the lid. The connecting element is mounted insuch a way that it lies on one side of the axis of pivoting of the lidwhen the lid is open, and on the other side of the axis of pivoting whenthe lid is closed. The connecting element undergoes elongation as itpasses from the open position to the closed position, and vice versa,the maximum extension being reached as the connecting element crossesthe axis of pivoting. This element can hold the lid in two extremepositions: in a fully open position or in a closed or almost closedposition, as desired.

The provisions mentioned hereinabove, namely the elastic band, theexternal coating of the pip or internal coating of the orifice, theovermoulding of the gripping regions and the annular gasket, may beachieved in a single manufacturing step using the duplex-injectionmethod, which consists in firstly injecting as one single part, in anappropriate mould, the cap hinged to the lid made of rigid material; andsecondly forming the elastic band, the coating of the pip or of theorifice, and overmoulding the gripping regions and making the annulargasket made of flexible thermoplastic.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to make the invention easier to understand, there will now bedescribed, by way of purely illustrative and non-limiting examples, twoembodiments of a dispensing cap according to the invention, withreference to the appended figures.

FIG. 1 depicts, in axial section, a dispensing assembly, opened,comprising a container fitted with a dispensing cap according to theinvention;

FIG. 2 depicts a view from above of the cap of FIG. 1;

FIG. 3 shows a view from above of an alternative form of the cap of FIG.1;

DISCUSSION OF THE PREFERRED EMBODIMENTS

With reference to FIG. 1, it is possible to see a dispensing assemblydenoted overall by the reference 1, comprising a container 21 having alongitudinal axis X, fitted with a dispensing cap 3 provided with a bodyreferenced 32. The container 21 has a closed bottom 22, and at theopposite end from the bottom, a neck 2 with an external screw thread 24for attaching the cap body 32 to the container. For this, the cap bodyhas a cylindrical internal skirt 25 with an internal screw thread thatcomplements the screw thread 24 on the neck 2. The container 21 has acircular or oval overall cross-section, this cross section may be anykind, for example polygonal or asymmetric. It is made, for example, ofhigh density polyethylene. The cap body, for its part, is made of arigid material, such as polypropylene.

The body 32 of the cap 3 has a plateau 34, provided over a portion ofits periphery, with a film hinge 8, via which a lid 5 is articulated,allowing this lid to pivot about an axis A constituting the axis of thehinge. The lid 5 has the shape of a cup with a peripheral edge 51 facingtowards the container. Provided in the plateau 34, on the opposite sideto the hinge 8 and in a plane passing through the hinge and through theaxis X of the container 21, there is a dispensing orifice 4. The orifice4 is defined by a cylindrical nozzle 41, 42 extending on either side ofthe plateau 34. An emerging part 41 of the nozzle has a conical internalshape, widening towards the outside. This nozzle constitutes a flowreducer, the emerging part 41 acting as a pouring spout.

The hinge 8 is formed in two parts 8 a, 8 b separated by an opening 8 c.Two orientation strips 12, 13 parallel to the axis A pass through theopening. These strips 12, 13 are embedded in a flat band 10 ofelastomeric material and constitute means of anchoring the band. Theends of this band are secured to the body 32 of the cap and to the lid 5respectively, this band 10 being secured to the body 32 and to the lid 5by fusion of the respective materials during manufacture of the cap 3.In order to strengthen further the anchorage of the band 10, additionalanchoring points 14 may be provided on each adjacent part at the ends ofthe band 10.

This band 10 is mounted in such a way that it lies on one side of theaxis A when the lid 5 is open, and on the other side of the axis A whenthe lid is closed. Thus the band 10 undergoes elongation as it passesfrom one of the positions to the other, the maximum elongation beingreached when the band 10 crosses the axis A. Once it has passed throughthe area of maximum elongation, the lid 5 is returned either to its openposition, or to its closed or almost closed position using a “toggleeffect”. From the almost closed position, the lid 5 can be closedcompletely by making the pip 6 enter the orifice 4, under friction. Theflexible band 10 is made, for example, of a blend ofpolypropylene/styrene-ethylene-butylene-styrene block polymer.

The dispensing orifice 4 is stoppered, when the lid is slipped down, bya pip 6 closing off the tubular part 41. This pip 6 is hollow and has anexternal coating 72 of flexible material. The inside diameter of thetubular part 41 and the outside diameter of the coating 72 are chosen tobe such that the pip 6 can enter the orifice 4 in a sealed way, underfriction, when the lid 5 is closed. Advantageously, this diameter is ofthe order of 3 to 8 mm, and depends on the viscosity of the product tobe dispensed. Typically, this viscosity lies within the range from 50mPa.s to 5 Pa.s.

It is of course possible to make a separate part in the form of acylindrical sleeve made of elastomer, the inside diameter of which isslightly smaller than the diameter of the pip. After the sleeve has beendrawn out radially, it can be placed over the pip and is held in placeby elasticity.

As can be seen in FIGS. 1 and 2, the inside 71 of the pip 6 may befilled with an elastomeric material.

As illustrated, especially in FIG. 2, the plateau 34 also comprises, atits periphery, an annular gasket 11 made of elastomeric material. It isarranged in such a way that the edge 51 of the lid 5 comes to restagainst this gasket 11, when the cap is closed.

On the opposite side to the hinge 8, the skirt 37 has a depressed region95 in the shape of an arc of a circle for example, making the lid 5easier to grip and to open. The surface 96 of this region is coveredwith a layer of flexible material. Likewise, the lid 5 has a grippingregion 91 in the form of a concave return 9, this region being covered,also, with flexible material. The use of a flexible material for thegripping regions gives the user an agreeable feel and makes the cap easyto manipulate. By selecting a particular flexible material, for exampleSANTOPRENE® (blend of polypropylene with terpolymers of ethylene,propylene and a diene (EPDM)), marketed by the company AES, it is evenpossible to obtain a “non-slip” effect which is advantageous when theuser is using a surfactant bodywash product in the shower or in thebath.

FIG. 3 shows a view similar to that of FIG. 2, illustrating analternative form of the stoppering pip. In this embodiment, a cap 103has a lid 105 with a pip 106. This pip has an elongate cross-section,curved into the shape of a “kidney bean”. It has an external coating 172of flexible elastomeric material. The corresponding orifice 104 has acomplementary shape, which means that the pip can enter this orificeunder friction. The kidney bean shape of the orifice 104 and of the pip106 is given merely by way of example. According to the invention, anyother conceivable shape may be envisaged.

The way of producing the cap according to the invention is very simple,allowing it to be manufactured in a single short moulding cycle byinjecting the two materials, rigid and flexible, in turn. This cap cantherefore be manufactured at an attractive cost.

What is claimed is:
 1. Dispensing cap intended to be fitted to acontainer containing a fluid product, comprising: a body provided with adispensing orifice; a hinged lid articulated to the body about an axis,the body and the lid being made of a rigid or semi-rigid material, saidlid being provided with a plugging pip intended to plug the dispensingorifice, when the lid is closed; and a coating of elastomeric materialarranged on the outer wall of the pip, to product a seal between the pipand the orifice when the lid is closed, wherein the pip is hollow andfull of elastomeric material.
 2. Cap according to claim 1, wherein theorifice has a cross-sectional shape taken from the group consisting ofcircular, oval, polygonal and elongate the cross-section of the pipcomplementing that of the orifice.
 3. Cap according to claim 1, whereinthe rigid or semi-rigid material is chosen from the group consisting ofpolypropylenes and polyethylenes.
 4. Cap according to claim 1,characterized in that the elastomeric material is a thermoplasticelastomer physico-chemically compatible with the rigid or semi-rigidmaterial, so as to allow a link by fusion with the rigid or semi-rigidmaterial, the said coating being deposited on the outer wall of the pipby dual injection or overmoulding.
 5. Cap according to claim 1,characterized in that the elastomeric material is chosen from the groupof elastomers of propylene/ethylene copolymers; polyether block amides;polyvinyls; terpolymers of ethylene, propylene and a diene;styrene-butadiene block copolymers; styrene-ethylene-butadiene blockcopolymers; thermoplastic polyurethanes; blends of polypropylene withone of the following elastomers: styrene-ethylene-butadiene blockpolymers; terpolymers of ethylene, propylene and a diene;styrene-butadiene block copolymers.
 6. Cap according to claim 1,characterized in that the said coating forms an attached part depositedon the outer wall of the pip by assembly.
 7. Cap according to claim 6,wherein the attached part is mounted by one from the group consisting ofsnap-fastening, bonding, welding, drawing and upset heading.
 8. Capaccording to claim 1, characterized in that the said coating has athickness of from 0.1 mn to 3 mn.
 9. Cap according to claim 1, whereinthe coating has a hardness from 20 Shore A to 90 Shore A.
 10. Capaccording to claim 1, characterized in that the body and/or the lid isprovided a gripping region covered with a layer of elastomeric material.11. Cap according to claim 1, characterized in that the body comprisesan annular gasket made of flexible material, in sealed contact with aperipheral edge of the lid, when the lid is flipped down.
 12. Capaccording to claim 1, characterized in that the lid is articulated tothe body by means of a hinge.
 13. Cap according to claim 1,characterized in that it comprises at least one connecting element madeof elastomeric material, forming a spring, one of the ends of theconnecting element being connected to the body, the other beingconnected to the lid, the connecting element being mounted in such a waythat it lies on one side of the axis A when the lid is open, and on theother side of the axis A when the lid is closed, the connecting elementundergoing elongation as it changes from one position to the other, themaximum extension being reached as the connecting element crosses theaxis.
 14. Assembly for dispensing a fluid product, comprising acontainer containing a fluid product, equipped with a dispensing cap,characterized in that the cap is a cap in accordance with claim
 1. 15.Cap according to claim 2, characterized in that the rigid or semi-rigidmaterial is chosen from polypropylenes or polyethylenes.
 16. Capaccording to claim 2, characterized in that the elastomeric material isa thermoplastic elastomer physico-chemically compatible with the rigidor semi-rigid material, so as to allow a link by fusion with the rigidor semi-rigid material, the said coating being deposited on the outerwall of the pip by dual injection or overmoulding.
 17. Cap according toclaim 3, characterized in that the elastomeric material is athermoplastic elastomer physico-chemically compatible with the rigid orsemi-rigid material, so as to allow a link by fusion with the rigid orsemi-rigid material, the said coating being deposited on the outer wallof the pip by dual injection or overmoulding.
 18. Cap according to claim2, characterized in that the elastomeric material is chosen from thegroup of elastomers of propylene/ethylene copolymers; polyether blockamides; polyvinyls; terpolymers of ethylene, propylene and a diene;styrene-butadiene block copolymers; styrene-ethylene-butadiene blockcopolymers; thermoplastic polyurethanes; blends of polypropylene withone of the following elastomers: styrene-ethylene-butadiene blockpolymers; terpolymers of ethylene, propylene and a diene;styrene-butadiene block copolymers.
 19. Cap according to claim 3,characterized in that the elastomeric material is chosen from the groupof elastomers of propylene/ethylene copolymers; polyether block amides;polyvinyls; terpolymers of ethylene, propylene and a diene;styrene-butadiene block copolymers; styrene-ethylene-butadiene blockcopolymers; thermoplastic polyurethanes; blends of polypropylene withone of the following elastomers: styrene-ethylene-butadiene blockpolymers; terpolymers of ethylene, propylene and a diene;styrene-butadiene block copolymers.
 20. Dispensing cap intended to befitted to a container containing a fluid product, comprising: a bodyprovided with a dispensing orifice; a hinged lid articulated to the bodyabout an axis, the body and the lid being made of a rigid or semi-rigidmaterial, said lid being provided with a plugging pip sized andconfigured to enter with friction into the dispensing orifice so as toplug said orifice, when the lid is closed; and a coating of elastomericmaterial arranged on at least the outer wall of the pip, to produce aseal between the pip and the orifice when the lid is closed, wherein thecoating of the outer wall of the pip is made by dual injection orovermolding, said elastomeric material being selected from the group ofelastic materials physicochemically compatible with said rigid orsemi-rigid material.
 21. Dispensing cap according to claim 20, whereinsaid elastic material forms a link with said rigid or semi-rigidmaterial by thermo-fusion.
 22. Dispensing cap according to claim 20,wherein said dispensing cap is molded in a single molding cycle.